Diabetic myonecrosis complicated by emphysematous pyomyositis and abscess caused by Escherichia coli: a case report.

BACKGROUND: Necrotizing myopathies and muscle necrosis can be caused by immune-mediated mechanisms, drugs, ischemia, and infections, and differential diagnosis may be challenging. CASE PRESENTATION: We describe a case of diabetic myonecrosis complicated by pyomyositis and abscess caused by Escherichia coli. A white woman in her late forties was admitted to the hospital with a 1.5 week history of bilateral swelling, weakness, and mild pain of the lower extremities and inability to walk. She had a history of type 1 diabetes complicated by diabetic retinopathy, neuropathy, nephropathy, and end-stage renal disease. C-reactive protein was 203 mg/l, while creatinine kinase was only mildly elevated to 700 IU/l. Magnetic resonance imaging of her lower limb muscles showed extensive edema, and muscle biopsy was suggestive of necrotizing myopathy with mild inflammation. No myositis-associated or myositis-specific antibodies were detected. Initially, she was suspected to have seronegative immune-mediated necrotizing myopathy, but later her condition was considered to be explained better by diabetic myonecrosis with multifocal involvement. Her symptoms alleviated without any immunosuppressive treatment. After a month, she developed new-onset and more severe symptoms in her right posterior thigh. She was diagnosed with emphysematous urinary tract infection and emphysematous myositis and abscess of the right hamstring muscle. Bacterial cultures of drained pus from abscess and urine were positive for Escherichia coli. In addition to abscess drainage, she received two 3-4-week courses of intravenous antibiotics. In the discussion, we compare the symptoms and findings typically found in pyomyositis, immune-mediated necrotizing myopathy, and diabetic myonecrosis (spontaneous ischemic necrosis of skeletal muscle among people with diabetes). All of these diseases may cause muscle weakness and pain, muscle edema in imaging, and muscle necrosis. However, many differences exist in their clinical presentation, imaging, histology, and extramuscular symptoms, which can be useful in determining diagnosis. As pyomyositis often occurs in muscles with pre-existing pathologies, the ischemic muscle has likely served as a favorable breeding ground for the E. coli in our case. CONCLUSIONS: Identifying the etiology of necrotizing myopathy is a diagnostic challenge and often requires a multidisciplinary assessment of internists, pathologists, and radiologists. Moreover, the presence of two rare conditions concomitantly is possible in cases with atypical features.

Rapidly fatal tropical pyomyositis in an elderly diabetic woman.

Necrotizing soft tissue infection, with or without myositis, is classified among the most dangerous infectious emergencies in clinical practice. The authors report a case of an older diabetic woman who presented to the orthopedic service with right elbow pain after a small trauma with skin abrasion and released with an analgesic prescription. After 48h, she presented to the emergency room with a history of developing bullous and necrotic lesions in the upper right limb, hypotension, and numbness, with rapid and fatal evolution despite adequate clinical and surgical therapeutic support. Muscle biopsy showed necrotizing myositis. Blood culture was positive for Panton-Valentine leukocidin producing (PVL-positive) methicillin-resistant S. aureus. Although PVL has a strong epidemiologic association with Community-Acquired Methicillin-resistant Staphylococcus aureus (CA-MRSA) infections, it can also be found in CA-MSSA in the context of necrotizing pneumonia and skin and soft tissue infections. Although infrequent, CA-MRSA or CA-MSSA PVL+ infections should always be suspected in high-risk patients because they can rapidly evolve with severe, sometimes fatal complications.

Piomiositis en niños: experiencia en un hospital pediátrico de referencia en Argentina / Pediatric pyomyositis: experience in a Pediatric Reference Center in Argentina

Resumen Introducción: La piomiositis es la infección del músculo esquelético, entidad poco frecuente en pediatría. Objetivo: Describir las características de 21 niños con piomiositis. Métodos: Estudio prospectivo-analítico de niños ingresados con diagnóstico de piomiositis entre mayo de 2016 y abril de 2017 en el Hospital de Niños Ricardo Gutiérrez, Buenos Aires, Argentina. Resultados: Tasa de hospitalización de 21,5/10.000 admisiones (IC 95% 4,65- 71,43). La mediana de edad fue de 5,4 años (rango 1,25-11,6). El 90,4% presentaba algún factor predisponente. La localización más frecuente fue en miembros inferiores. La proteína C reactiva (PCR) estuvo elevada en todos los pacientes, con una media de 124 mg/L (DS 96), siendo significativamente más elevada en los pacientes que tuvieron hemocultivos positivos 206 (DS 101) vs 98 (DS 81), (p = 0,02). Se obtuvo rescate microbiológico en 17 pacientes (80,9%): Staphylococcus aureus resistente a meticilina (SARM) (n: 15) y Streptococcus pyogenes (n: 2). Se presentó con bacteriemia 23,8% de los pacientes. El 81% requirió drenaje quirúrgico. Conclusión: Staphylococcus aureus RM adquirido en la comunidad (SARMAC) es el patógeno predominante. En la selección del tratamiento empírico adecuado debería tenerse en cuenta: el patrón de resistencia local y el valor de PCR.

Background: Pyomyositis is the infection of skeletal muscle, a rare pathology in children. Aim To describe the characteristics of pyomyositis in pediatric patients. Methods: Prospective analytical study of hospitalized children diagnosed with pyomyositis from May 2016 to April 2017 at the Ricardo Gutiérrez Children's Hospital, Buenos Aires, Argentina. Results: Twenty-one patients with pyomyositis were identified. Annual rate: 21.5/10,000 admissions (95% CI 4.65-71.43). The median age was 5.4 years (range 1.25-11.6). The lower limbs were the most affected site. C-reactive protein (CRP) was elevated in all patients, with a mean of 124 mg/L (SD 96), being significantly higher in patients with bacteremia: 206 (DS 101) vs 98 (DS 81), p = 0.02. Bacterial cultures were positive in 17/21 (80.9%): 15 methicillin-resistant Staphylococcus aureus (MRSA), and 2 Streptococcus pyogenes. Blood cultures were positive in 5 (23.8%). Conclusion: MRSA-community acquired is the predominant pathogen in our setting. In the selection of the appropriate empirical treatment, the local resistance pattern and the CRP value should be taken into account.

Tropical pyomyositis: diabetes facilitating the onset of an uncommon disease / Piomiosite tropical: diabetes facilitando o aparecimento de uma doença incomum

INTRODUCTION: Tropical pyomyositis is an infectious disease that affects skeletal muscle and may appear as a diffuse inflammation or a rapidly progressive myonecrotic process. The predisposition of this disease in diabetics is already mentioned in several studies. The pathogenesis is possibly related to changes in neutrophils and the reversal of the immune response pattern that occurs in situations such as parasitic diseases. Staphylococcus aureus is the most common microorganism, accounting for 90% of cases of tropical pyomyositis. The diagnosis is sometimes late because patients usually do not seek care by the first symptoms, and because it is a rare disease and physicians are not very familiar with it. CASE REPORT: A 42-year-old male patient with diabetes mellitus, hypothyroidism, anemia, thrombocytopenia, and hypoalbuminemia developed tropical pyomyositis with multiple muscle abscesses in quadriceps, soleus and anterior tibial, triceps and biceps brachialis and pronator round, requiring prolonged antibiotic therapy and surgical drainage. CONCLUSION: Pyomyositis is a little known disease and if not diagnosed early can be fatal.

INTRODUÇÃO: A piomiosite tropical é uma doença infecciosa que afeta o músculo esquelético, aparecendo como uma inflamação difusa ou um processo mionecrótico rapidamente progressivo. A predisposição desta enfermidade em diabéticos já é referida em vários estudos. A patogênese possivelmente está relacionada a alterações nos neutrófilos e na inversão do padrão de resposta imune que acontece em situações como parasitoses. Staphylococcus aureus é o microorganismo mais comum, representando 90% dos casos de piomiosite tropical. O diagnóstico pode ser tardio porque os pacientes geralmente não buscam cuidados com os primeiros sintomas e, por ser uma doença rara, pode surpreender um médico ainda não familiarizado com esta entidade clínica. RELATO DE CASO: Paciente do sexo masculino com 42 anos de idade com diabetes mellitus, hipotireoidismo, anemia, trombocitopenia e hipoalbuminemia que desenvolveu piomiosite tropical com múltiplos abscessos musculares em quadríceps, sóleo e tibial anterior, tríceps e bíceps braquial e pronador redondo, necessitando de antibioticoterapia prolongada e drenagem cirúrgica. CONCLUSÃO: A piomiosite não é uma doença bem conhecida e pode ser fatal se não for diagnosticada precocemente.

[Streptococcus pyogenes pyomyositis of the piriformis muscle in a child]. / Piomiositis del músculo piriforme porStreptococcus pyogenesen un niño.

Acute pyomyositis is a suppurative infection of the skeletal muscle. Staphylococcus aureus is the most frequent etiological agent. Cases produced by Streptococcus pyogenes are uncommon. The most usual locations are quadriceps, buttocks and iliopsoas. The involvement of the piriformis muscle is very exceptional. We present the case of a previously healthy 8-year-old male who was admitted to our hospital for acute pyomyositis caused by Streptococcus pyogenes located in the piriformis muscle. Early diagnosis and prompt initiation of antibiotic treatment allowed the conservative management of the condition, and surgery was not necessary. The evolution was satisfactory without sequels.

La piomiositis aguda es una infección supurativa del músculo esquelético. El agente etiológico más frecuente es Staphylococcus aureus, y son infrecuentes los casos producidos por Streptococcus pyogenes. Las localizaciones más habituales son cuádriceps, glúteos e iliopsoas; es excepcional la afectación del músculo piriforme. Se presenta el caso de un varón de 8 años, previamente sano, que fue ingresado en nuestro hospital por una piomiositis aguda por Streptococcus pyogenes localizada en el músculo piriforme. El diagnóstico y el inicio precoz del tratamiento antibiótico permitieron el manejo conservador del cuadro y no fue necesaria la cirugía. La evolución fue satisfactoria y no presentó secuelas.

Subscapularis pyomyositis: a rare presentation of shoulder pain.

We present a rare case of a subscapularis pyomyositis in a 38-year-old woman and examine the diagnostic and surgical challenges posed. History and examination features were similar to that of septic shoulder arthritis without overlying features of warmth or erythema. Serological markers revealed a C-reactive protein of 221 mg/L and white cell count of 11.1×109/L. A dry shoulder aspirate was obtained. Contrast-enhanced MRI demonstrated a peripheral rim-enhancing lesion within the subscapularis muscle belly with lack of central enhancement. These features are consistently seen with an infective aetiology. A deltopectoral approach to surgical drainage was utilised and subsequent fluid cultures grew Panton-Valentine Leukocidin positive Staphylococcus aureus species. This rare bacterium is associated with an increased risk of osteomyelitis and despite making a full recovery, the patient was advised to reattend if any future shoulder pain was encountered.

Aspergillus myofasciitis in a chronic granulomatous disease patient: first case report.

Aspergillus myofasciitis is a rare infection of the muscles and their fascial sheaths that has been reported in patients with immune deficiencies of various kinds but, until now, not with chronic granulomatous disease (CGD). Patients affected by CGD are at high risk of invasive aspergillus infections. The case described involves a 14-year-old boy with a severe autosomal recessive CGD who was admitted to hospital with an Aspergillus myofasciitis of the left forearm. He was treated with liposomal amphotericin for 14 days and then with oral voriconazole for three months with an excellent clinical outcome. He did not evidence any recurrence in the following 30 months using itraconazole prophylaxis.

Pyomyositis caused by Streptococcus pneumoniae after allogeneic hematopoietic stem cell transplantation.

Pyomyositis is classified into two main types: tropical and non-tropical. Non-tropical pyomyositis occurs among various immunocompromised patients, and Staphylococcus aureus has been reported as the most common pathogen. Pyomyositis caused by Streptococcus pneumoniae is uncommon, and has not been previously reported after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Here, we report a unique case with pyomyositis caused by S. pneumoniae in the bilateral erector spinae muscles 34 months after allo-HSCT. The patient had an initial clinical response following the administration of intravenous benzylpenicillin potassium for 4 weeks. Although S. pneumoniae bacteremia is a rare bacterial infection after HSCT, the possibility of pyomyositis must be considered when a recipient develops S. pneumoniae bacteremia. Accurate diagnosis and the selection of appropriate antibiotics are necessary for the treatment of pyomyositis.

Update in Pediatric Musculoskeletal Infections: When It Is, When It Isn't, and What to Do.

Musculoskeletal infections, including osteomyelitis, septic arthritis, and pyomyositis, are a substantial cause of morbidity in children and adolescents. The increased virulence of infectious agents and the increased prevalence of antimicrobial-resistant pathogens, particularly methicillin-resistant Staphylococcus aureus, have resulted in a more complicated clinical course for diagnosis and management, which is evidenced by an increased length of hospital stays, incidence of complications, and number of surgical interventions. Musculoskeletal infections are a challenge for surgeons because they vary substantially in their presentation and in their required treatment, which is based on the causative organism, the location of the infection, and the age of the patient. The necessity for a prompt diagnosis is complicated by several diseases that may mimic musculoskeletal infection, including transient synovitis, autoimmune arthritis, and tumors. Recent innovations in diagnosis and management have provided surgeons with new options to differentiate musculoskeletal infections from these rapidly evolving disease pathologies. As diagnostic and treatment modalities improve, collaboration among surgeons from multiple disciplines is required to develop evidence-based clinical practice guidelines that minimize the effect of musculoskeletal infection and optimize clinical outcomes for patients.

Piomiositis primaria: Revisión de 32 casos diagnosticados por ecografía / Primary pyomyositis. Review of 32 cases diagnosed by ultrasound

La piomiositis primaria es la infección bacteriana por vía hematógena del músculo estriado. Está relacionada con factores de riesgo como HIV/sida y otras enfermedades inmunodepresoras, pudiendo estar asociados a factores locales de estrés muscular. El agente etiológico más frecuente es Staphylococcus aureus. Su retardo diagnóstico puede ocasionar una evolución fatal. En esta serie se evaluaron 32 pacientes con piomiositis primaria diagnosticados por ecografía. El factor de riesgo más frecuente fue el HIV/sida (61%). Los factores locales se detectaron en 21 casos (66%): en primer lugar, la práctica de futbol. La forma monofocal se observó en 19 (59%) los músculos más frecuentemente afectados fueron cuádriceps, gemelos y psoas. Se obtuvieron muestras para estudio bacteriológico en 30 casos, 27 de material del absceso y 22 hemocultivos. En los 30 casos se aisló el agente etiológico. El Staphylococcus aureus representó el 83.3% (25 casos) y Escherichia coli, Nocardia spp., Streptococcus agalactiae, Micobacteria no tuberculosa y Pseudomonas aeruginosa fueron aislados en un caso cada uno. Recibieron tratamiento quirúrgico 17 pacientes, punciones aspirativas, 9; antibióticos solamente, 4. Presentaron buena evolución 28 de los 30 pacientes (93.3%), óbitos, 2 (6.6%); desconocida, 2. Este estudio concluyó que: ante la etiología diversa y cambiante de las piomiositis primarias es importante reconocer el agente involucrado y su sensibilidad antibiótica. La ecografía realiza la evaluación en tiempo real y puede ser utilizada como guía de punción facilitando el diagnóstico inmediato. Esto la diferencia de otras técnicas, transformándola en un método de primera línea para el estudio de esta enfermedad.

Primary pyomyositis is a bacterial infection of striated muscle which is acquired by hematogenous route. It is related to risk factors such as HIV/aids and other immuno suppressing diseases, and can be associated with local muscle stress factors. The most frequent etiology is Staphylococcus aureus. Its diagnostic delay may cause a fatal evolution. In this series 32 patients with primary pyomyositis diagnosed by ultrasound were evaluated. The most frequent risk factor was HIV/aids (61%). Local factors were detected in 21 (66%) cases: first, the practice of football. The monofocal form was observed in 19 (59%), the most commonly affected muscles were quadriceps, calves and psoas. Samples for bacteriological study were obtained in 30 cases, 22 blood culture and 27 abscess materials. In 30 cases the etiologic agent was isolated. Staphylococcus aureus accounted for 83.3% (25 cases) and Escherichia coli, Nocardia spp., Streptococcus agalactiae, nontuberculous mycobacteria, Pseudomonas aeruginosa were isolated in one case each. Seventeen patients received surgical treatment, aspirative punctures, 9; antibiotics alone, 4. Twenty eight (93.3%) patients had a good evolution; deaths, 2 (6.6%); unknown, 2. Main conclusions of this study were: due to the diverse and changing etiology of the primary pyomyositis it is important to recognize the etiological agent involved and their antibiotic susceptibility.The ultrasound performed the study in real time so it can be used to guide the puncture and to facilitate the immediate diagnosis. This makes the difference with other techniques and transforms it into a first-line method for the study of this disease.

Acromioclavicular septic arthritis and sternoclavicular septic arthritis with contiguous pyomyositis.

Acromioclavicular (AC) and sternoclavicular (SC) septic arthritis with contiguous pyomyositis are rare, especially in immunocompetent individuals. We report a case of septic AC joint with pyomyositis of the deltoid and supraspinatus muscles and a separate case with septic SC joint with pyomysitis of the sternocleidomastoid muscle. Both patients had similar presentations of infections with Staphylococcus aureus and were successfully treated with surgical incision and drainage followed by prolonged antibiotic therapy.

Microbiological culture methods for pediatric musculoskeletal infection: a guideline for optimal use.

BACKGROUND: Culture results affect the diagnosis and treatment of children with musculoskeletal infection. To our knowledge, no previous large-scale study has assessed the relative value of culture methods employed during the evaluation of these conditions. The purpose of this study was to identify an optimal culture strategy for pediatric musculoskeletal infection. METHODS: Children with musculoskeletal infection were retrospectively studied to assess culture results from the infection site or blood; culture type, including aerobic, anaerobic, fungal, and acid-fast bacteria (AFB); antibiotic exposure history; and clinical history of children with positive culture results. RESULTS: We studied 869 children, including 353 with osteomyelitis, 199 with septic arthritis, forty-two with pyomyositis, and 275 with abscess. The 4537 cultures processed included 1303 aerobic, 903 anaerobic, 340 fungal, 289 AFB, and 1702 blood. Of 3004 specimens sent during initial work-up, positive results occurred in 677 of 1049 aerobic cultures (64.5%), 140 of 763 blood cultures (18.3%), eighteen of 722 anaerobic cultures (2.5%), five of 251 fungal cultures (2.0%), and two of 219 AFB cultures (0.9%). Staphylococcus aureus was the most common pathogen isolated, from 428 (50.7%) of 844 children for whom blood or infection-site culture material was sent (methicillin-resistant S. aureus, 252; and oxacillin-sensitive S. aureus, 176). Cultures were negative in 206 (29.0%) of the 710 children for whom culture material from the site of infection was sent. Children with true-positive anaerobic, fungal, or AFB cultures had a history of immunocompromise, penetrating inoculation, or failed primary treatment. Antibiotic exposure prior to culture-sample acquisition did not interfere with aerobic culture results from the site of infection. CONCLUSIONS: Our findings suggest that anaerobic, fungal, and AFB cultures should not be routinely performed during the initial evaluation of children with hematogenous musculoskeletal infection. These cultures should be performed for children with immunocompromise, clinical suspicion of penetrating inoculation, or failed primary treatment.

Visual diagnosis: 11-year-old boy with leukemia, fever, elbow, and leg pain.

The diagnosis of pyomyositis requires a high index of suspicion in patients with hematologic malignant neoplasms. Correct diagnosis might be delayed initially because of vague clinical presentation, overlapping symptoms, and nonspecific clinical signs. Pyomyositis should be included in the differential diagnosis when a patient develops swollen or tender muscles after chemotherapy with or without bacteremia. Prompt treatment with broad-spectrum antibiotics that cover S aureus and resistant emerging gram-negative organisms, specifically E coli, should be initiated immediately in patients with hematologic illnesses along with close monitoring and follow-up.

Primary pyomyositis and disseminated septic pulmonary emboli: a reactivated staphylococcal infection?

Staphylococcal pyomyositis is a severe invasive soft tissue infection with high mortality rate that is increasingly being recognized even in temperate climates. In most cases predisposing factors are identified that include either source of skin penetration or/and impaired host immunocompetence. A case of primary, community-acquired pyomyositis of the left iliopsoas muscle in a 59-year-old immunecompetent woman, which was complicated with septic pulmonary emboli within 24 h after hospital admission, is presented. The patient was subjected to abscess drainage under computed tomography guidance. Both pus aspiration and blood cultures revealed methicillin-susceptible Staphylococcus aureus. Given the absolute absence of predisposing factors and a remote history of staphylococcal osteomyelitis in the same anatomical region 53 years ago, reactivation of a staphylococcal soft tissue infection was postulated. Systematic review of the literature revealed a few interesting cases of reactivated staphylococcal infection after decades of latency, although the exact pathophysiological mechanisms still need to be elucidated.

Enterobacter cloacae pyomyositis complicating chronic granulomatous disease and review of gram-negative bacilli pyomyositis.

Pyomyositis is a primary purulent infection of skeletal muscles mostly described in tropical areas. Staphylococcus aureus is by far the main causative microorganisms. In temperate areas, pyomyositis more frequently affects male adults with immunodeficiency. Gram-negative bacilli pyomyositis are uncommon and occur mainly in this context of immunodeficiency. Only one case of Enterobacter cloacae pyomyositis has been reported so far. Chronic Granulomatous Disease (CGD) is a rare inherited immunodeficiency characterized by a loss of NADPH oxidase activity in phagocytic cells that favors infections due to catalase-positive microorganisms. Pyomyositis has only been described once as a complication of CGD. We report here a case of Enterobacter cloacae-associated pyomyositis of the left thigh in a patient with CGD, and review the literature on Gram-negative pyomyositis.